Beta-carbonyl-substituted ureides



BETA-CARBGNYL-SUBSTITUTED UREIDES David E. Adelson, Berkeley, Calif., assignor to Shell Development Company, Ezneryville, Calif., a corporation of Delaware N Drawing. Application October 13, 1951, Serial No. 251,240

16 Claims. (Cl. 260-482) This invention relates to a new method of producing allophanyl-substituted compounds which have valuable properties and also deals with the novel products of this reaction.

The allophanyl-substituted compounds with which the invention is concerned are those having the allophanyl group 0 0 NH2( ]NH directly linked to a carbon atom. It has been found, unexpectedly, that compounds of this type can be produced advantageously by reacting biuret with organic compounds having a labile hydrogen atom attached to a carbon atom of the molecule. The reaction is carried out under conditions at which ammonia is split off and the corresponding allophanyl compound is produced.

There are a number of different labile hydrogen-containing compounds which may be used in the process successfully. The reaction of biuret with hydrocarbons having a labile hydrogen atom is claimed in my copending application Serial No. 93,629, filed May 16, 1949, now U. S. Patent 2,576,895, of which the present application is a continuation-in-part. The present application is also a continuation-in-part of copending application of Adelson and Larsen, Serial No. 46,558, filed August 27, 1948, now U. S. Patent 2,599,736.

Instead of the hydrocarbons, substitution products thereof having a labile hydrogen atom may be used provided the substituent or substituents are non-reactive under the conditions used. it has been found that substituents such, for instance, as the halogens, particularly fluorine and chlorine, nitro groups, ether, ester and keto groups, and the like are non-reactive under the conditions preferred for carrying out the new process and may be present in the starting labile hydrogen-containing compound without interfering with the desired formation of the allophanyl compound.

The sub-group of labile hydrogen-containing compounds, which are particularly useful starting materials for use in the process according to the present invention, is the carbonyl compounds having a hydrogen atom (the labile hydrogen) attached to a carbon atom directly linked to the carbonyl carbon atom. Included among these compounds are, for example, the carboxylic acids and their esters and the ketones having a labile hydrogen atom. Especially suitable are compounds of this type having two carbonyl groups which are linked together by a single carbon atom to which a hydrogen atom is attached since the labile hy rogen atom is particularly reactive with biuret in such cases. Typical compounds of this type are, for instance, the malonates including substituted malonates, especially mono-alkyl malonic acid esters, glutaconic acid and its esters, beta-ketonic carboxylic acids and their esters of which acetoacetic ester is typical, and the beta-diketones which may be aliphatic, alicyclic, aromatic or carbocyclic. In many cases these compounds also are substituted by alkali metals such as sodium or potassium at the labile hydrogen atom which may be either on a methylene or a saturated methenyl or methylidyne group. instead of the dicarbonylic compounds, the somewhat less reactive corresponding monocarbonylic acids, esters and hetones may be similarly used. in all cases compounds having non-reactive substituents such as those previously discussed in connection with the labile hydrogen-containing hydrocarbons may be used successfully instead of the corresponding monoor poly-carbonyl compounds.

T he chosen labile hydrogen-containing reactant may be a pure or substantially pure chemical compound or a mixture of two or more such compounds or a mixture of one or a plurality of labile hydrogen-containing compounds with other compounds which do not interfere with the reaction. Also, it is frequently advantageous in the interest of economy to use the labile hydrogen-containing compound in the crude form in which it naturally occurs or is initially produced, or as incompletely refined products from such sources containing other components which do not interfere with the reaction of the invention.

The conditions under which the reaction of biuret with the chosenlabile hydrogen-containing compound or compounds is carried out will depend upon the particular labile hydrogen-containing carbonyl compounds used. As a general rule, an elevated temperature of at least C. is desirable and preferably temperatures of C. to 250 C. are used, although higher temperatures up to the decomposition temperature of the product but preferably below 350 C. can be employed. The time of reaction will depend upon the temperature which is chosen and will be longer for lower temperatures than when temperatures nearer the upper limit of the permissible range are used. Also, longer times of reaction are desirable when using the less reactive labile hydrogen-containing compounds such as isoparatfin or mono'ketones than when employing compounds which form alkali metal substitution products such as fiuorene, diethyl malonate, etc.

As a general rule, it is desirable to carry out the reaction under conditions at which the ammonia produced is removed substantially as fast as it is formed in the reaction. To this end, it is advantageous to operate at a subatmospheric pressure. Most preferably, however, pressures are used at which both reactants are maintained in the liquid. However, the use of conditions under which the labile hydrogen-containing carbonyl compound is volatilized is not excluded since, by passing the exit gases through a condenser or reflux column or by other suitable means, any unreacted labile hydrogen-containing carbonyl compound present in the effluent can be recovered and returned to the reaction. Such procedure is especially applicable in the case of highly volatile reactants such as acetone, for example. it is feasible in such, as well as other, cases to carry out the reaction in the gaseous state. Also, atmospheric or subatmospheric pressure may be used in both liquid and gas phase operations. As a general rule, however, it is preferred to operate in the liquid phase with pressures below 500 mm. Hg absolute, most preferably at pressures below 250 mm. Hg. Pressures of the order of about 1 to 20 mm. Hg have been found to be especially advantageous as products of superior quality and best color are usually obtained by operating in this range.

The ratio of the reactants which it will be most desirable to use will depend upon the particular labile hydrogen-containing carbonyl compound chosen for reaction but, as a general rule, a stoichiometric excess of biuret over that required for reaction with the labile hydrogen present in preferred. Usually a mole ratio of biuret to labile hydrogen-containing carbonyl compound of the order of 1.2:1 to 3:1 is preferred, although lower or higher ratios may be employed.

in some cases it is desirable to carry out the reaction in the presence or a mutual solvent for the biuret and labile hydrogen-containing carbonyl compound since intimate contact of the reactants can be facilitated in this way and better control of the reaction can be achieved. Suitable mutual solvents are those which are nonreactive under the chosen conditions. For labile hydrogen-containing carbonyl compounds which are soluble in hydrocarbons, solvents such as normal paraffins, e. g. hexane, heptane, octane, decane, octane, etc., aromatics such as benzene, toluene and like compounds free from labile hydrogen atoms are useful.

The process may be carried out batchwise, intermittently or continuously, continuous operation being most advantageous for large scale manufacture. Any suitable form of equipment or apparatus may be used to carry out the reaction. It is desirable in many cases to provide means for agitating the contents of the reaction vessel by shaking, stirring, agitating with an inert gas, etc. As previously pointed out, where low boiling materials are used as reactants, it is desirable to fit the reaction vessel with a condenser or suitable reflux equipment to avoid loss of material. Suitable heating means may also be employed in order to maintain the reactants at the desired or optimum temperature. Although ammonia gas evolved may be vented to the atmosphere, it is often desirable to provide suitable apparatus for catching and recovering the ammonia gas emanating from the reaction mixture.

A number of dilferent methods of working up the reaction product for recovery of the allophanyl compound produced are available. Thus, the product may be isolated and purified by distillation, extraction, fractionation, crystallization or any other suitable process. A preferred method for recovering the product is to cool the reaction mixture and then treat it with a solvent in which the allophanyl compound is soluble to the substantial exclusion of the other components of the mixture, especially of the biuret which may be present in excess of the theoretical amount required. Any solvent which preferentially dissolves the allophanyl compound and does not react with it may be used for the extraction. Suitable solvents are the hydrocarbon solvents, the alcohols, the ethers, the ketones, certain esters and the like. Toluene and the hot acid octane have been found to be especially suitable solvents to use for isolating and purifying the allophanyl compounds.

The process of the invention is illustrated by the following examples which also show some of the many valuable new compounds obtainable according to the invention.

EXAMPLE I Biuret and diethyl malonate (molar ratio :1) are heated and stirred for 46 hours at 139 C.-l42 C. and 95-145 mm. pressure. After extraction with n-butyl acetate, the product is isolated as a viscous, ambercolored liquid which is slightly soluble in western lubricating oil, SAE grade, and which analyzes as follows:

Calculated For Fmmd Nrno ounooomooooznei Percent Nitrogen. l2. 7 11. 4 1t 20/D *1. 467 (2) Acid value equiv The refractive index (n 20/D) of diethyl malonate is reported to be 1.4143.

EXAMPLE II Acetoacetic ethyl ester heated at 150 C. with 3 moles of biuret under a pressure of 350 mm. Hg for 43 hours gives a good yield of alpha-allophanyl acet'oacetic acid ethyl ester In the same way, biuret reacts with ethyl a'eetoaceufe methyl ester to give alpha,alpha-allophanyl methyl. acetor acetic methyl ester Acetylrnalonic and ketosuccinic acid esters react in the same way under the same conditions. With ketoglutaric acid esters, however, diallophanyl derivatives are also formed unless a substantial molar excess of. ester to biuret is used. Thus, from beta-ketoglutaric acid ester one can obtain alpha-allophanyl beta-ketoglt'itaric acid ester A mixture of about 5 parts by weight of dibenzoyl methane and 7 parts of biuret of about purity reacted for 23 hours at C. to C. while maintaining a pressure of 100 to mm. Hg and taking off the evolved gases, mainly ammonia, through a sulfuric acid trap, gives a good yields of allophanyl dibenzoyl methane I t i Q H2N--NHC-( JH Under the same conditions 3-allophanyl-2,4-nouane dione (I) O l-CH3 HzN-lib-NH-iL-CH is obtained from acetyl caproyl methane, and allophanyl benzoyl acetyl methane is obtained from benzoyl acetone.

EXAMPLE 1v Reacting a mixture of benzyl-propyl ketone and biuret in a mole ratio of 2.5:1 at 133 C. and 130 mm. Hg gives 4-allophanyl-4-phenyl-3-butanone d-Carvone reacts similarly with biuret to produce allophanyl carvone From these illustrative examples it will be seen that the process of the invenL'on is applicable to a wide variety of difierent organic compounds having a carbonyl group linked directly to a carbon atom to which a labile hydrogen atom is directly attached. It will be understood, however, that the process is not limited to the compounds used by way of illustration in the examples since a great many other compounds are operative in the new reaction and produce valuable new products. Among such other useful starting materials are, for instance:

A. Kelones (1) ALIPHATIC (SATURATED AND UNSATURATED) B. Aldehydes (1) ALIPHATIC (SATURATED AND UNSATURATED) Acetaldehyde Oleyl valeraldehyde Propionaldehyde Succinic dialdehyde Butyraldehyde Acrolein Isobutyraldehyde Glutaric dialdehyde Caproaldehyde Adipic dialdehyde Valeraldehyde Levulinic aldehyde Crotonaldehyde Alpha-chloroglutaconic Citronellal dialdehyde 2 AROMATIC Phenyl acetaldehyde Diphenyl acetaldehyde Phenyl methyl acetaldehyde Benzyl acetaldehyde Cinnamaldehyde Tolyl acetaldehyde p-Chlorophenyl acetaldehyde C. Acids Acetic acid Pimelic acid Phenyl acetic acid Azelic acid Benzoyl acetic acid Brassylic acid Adipic acid Phenyl malonic acid Pyruvic acid Ethyl glycolic acid Propionyl acetic acid Thiodiglycolic acid Itaconic acid Beta-chloropropionic acid Chlorophenyl acetic acid ,Glutaconic acid Ethoxymalonic acid Malic acid Aspartic acid Butyrl formic acid Aceto butyric acid Levulinic acid IZ-keto stearic acid 13-keto behenic acid Aldovaleric acid Hexahydrobenzoic acid 1,2-cyclohexan0ne carboxylic acid D. Esters of carboxylic acids Esters of any of the foregoing carboxylic acids with any of the following alcohols:

Methyl alcohol Ethyl alcohol Propyl alcohol isopropyl alcohol Methallyl alcohol Crotyl alcohol 2-propyn-l-ol Oleyl alcohol n-Butyl alcohol Geraniol lsobutyl alcohol Citronellol Secondary butyl alcohol Linalool Diacetone alcohol Ethylene glycol monoethyl ether Cyclohexanol Naphthenic alcohols Benzyl alcohol Tolyl alcohol Phenyl ethyl alcohol Octadecylbenzyl alcohol Tertiary butyl alcohol Arnyl alcohol Hexyl alcohol Octyl alcohol Decyl alcohol Lauryl alcohol Myristyl alcohol Cetyl alcohol Stearyl alcohol Allyl alcohol Some of the specific esters which are operative in the process are:

Allyl acetate Allyl propionate Allyl laurate Allyl capronatc Allyl isovalerate Allyl stearate Ethyl propionylacetate ethyl acetobutyrate Methyl benzoylacetate Allyl alloxyacetic acid Methyl ricinoleate Di-sec-butyl diglycolate Triethyl rnethoxy citrate Dirnethyl sebacate Ethyl isobutyrate Dibutyl tartronate ethyl ether Dimethyl suberate Dimethyl azelate Dioctyl sebacate Dioctyl succinate Allyl methallyloxyacetate Glyceryl ricinoleate Glyceryl oleate Allyl succinate Sorbitan oleate Naturally occurring esters such as:

Castor oil Neats-foot oil Cocoauut oil Palm oil Corn oil Peanut oil Cottonseed oil Carnauba wax Horse fat Spermaceti Lard oil Beeswax Wool f at Rapeseed oil Japan wax Soya bean oil Mutton tallow Whale oil Beef tallow Sperm oil The products of the invention have many valuable properties which make them useful in a variety of industrially important applications. Those which are oil-soluble are, as a class, very valuable lubricating oil additives, as described in more detail and claimed in copending application of Adelson and Larsen, Serial No. 46,558, filed August 27, 1948, previously referred to. The new compounds are also useful antioxidants for natural and synthetic rubbers and other organic materials which are subject to oxidative deterioration, particularly fats and oils. Relatively small amounts are effective in retarding oxidation and, generally, it is not necessary to use more than by weight of the allophanyl compound, and preferably about 0.1% to 2% by weight when applying the new compounds as antioxidants.

The products having or more carbon atoms in a chain, such as alpha-allophanyl acetoacetic acid octadecyl ester and the like, have detergent and wetting properties and may be used in cleaning compositions, as textile treating agents, and in the preparation of emulsions and the like.

The allophanyl derivatives of ketones and esters are useful plasticizers and softeners for the artificial and natural resins with which they are compatible. The products from the unsaturated esters, for instance, alphaallophanyl diallyl or divinyl malonates, are capable of polymerization to useful resins, the copolymers with other polymerizable compounds such as vinyl chloride, vinyl acetate, diallyl phthalate, styrene, etc. being especially advantageous, particularly when the allophanyl ester represents about to by weight of the starting mixture of monomers.

The allophanyl ketone compounds of the invention,

such as 3-allophanyl-2-butanone, l-allophanyl-Z-propanone, 2-allophanylcyclohexanone, etc., undergo condensation with other ketones, for example, acetone. methyl ethyl ketone, mesityl oxide and the like, to produce resinous products varying from viscous liquids to hard, clear solids. The allophanyl derivatives of dicarboxylic acids, for instance, alpha-allophanyl malonic acid and the like, are useful starting materials for the preparation of alkyd resins by reaction. with polyhydroxy alcohols such as glycerine, ethylene glycol, polyvinyl alcohol, etc.-

By reaction with alcohols, whether monoor polyhydroxy, at temperatures of the order of 50 C. to 200 C., preferably under reduced pressure, the terminal amine group of the new compounds is split off as ammonia and is substituted by the oxy radical of the alcohol used, forming an ester linkage. Still other reactions may be carried out with the new compounds of the invention which will thus be seen to ofier many advantages in widely different applications. It will therefore be clear that the invention is not limited to the examples which are merely given as illustrative of the diverse compounds and their uses made possible by the invention.

I claim as my invention:

1. A process of producing a member of the group consisting of allophanyl-substituted ketones and carboxylic acid esters which comprises reacting biurct with a member of the group consisting of monoketones and diketones and monocarboxylic acid esters and dicarboxylic acid esters composed exclusively of carbon, hydrogen and oxygen chosen from the group consisting of ester and keto oxygen atoms, having a total of not more than 57 carbon atoms in the molecule and having a labile hydrogen atom attached to a carbon atom which is directly linked to a carbonyl carbon atom at a temperature of about 50 C. to about 350 C. whereby ammonia is formed and an allophanyl group is substituted for said labile hydrogen atom on said carbon atom.

2. A process in accordance with claim 1 wherein the said labile hydrogen atom is attached to a carbon atom to which two carbonyl carbon atoms are also directly linked and the reaction is carried out at between about C. and 250 C. using a molar excess of biuret.

3. A process of producing an allophanyl-substituted ester of a dicarboxylic acid which comprises heating an ester of a dicarboxylic acid containing no other atoms than carbon, hydrogen and carbonyl and ester-oxygen atoms and having a hydrogen atom directly attached to a carbon atom to which the two carboxyl carbon atoms of the acid are also directly attached, the hydrocarbon radicals of which ester each contain not more than 18 carbon atoms, with a molar excess of biuret at a temperature of 100 C. to 250 C. whereby ammonia is formed and an allophanyl group is substituted for hydrogen on said carbon atom.

4. A process of producing an allophanyl-substituted alkyl ester of a malonic acid which comprises heating at 50 C. to 250 C. an alkyl ester of a malonic acid having not more than 18 carbon atoms per alkyl group and containing no other atoms than carbon, hydrogen and carbonyl and ester-oxygen atoms and having a hydrogen atom directly attached to the carbon atom to which the two carboxyl carbon atoms of said acid are also directly attached with a molar excess of biuret and an allophanyl group is substituted for hydrogen on said carbon atoms, and removing the ammonia produced substantially as fast as it is formed.

5. A process which comprises heating at a temperature of 100 C. to 250 C. and a subatmospheric pressure diethyl malonate with a molar excess of biuret.

6. A process of producing an allophanyl-substituted keto-hydrocarbon which comprises heating at 50 C. to

250 C. a keto-hydrocarbon having directly attached to a carbonyl carbon atom a saturated carbon atom to which a hydrogen atom is directly linked, the hydrocarbon radicals joined to carbonyl carbon each containing not more than 18 carbon atoms, with biuret whereby ammonia is formed and an allophanyl group is substituted for hydrogen on said carbon atom.

7. A process of producing an allophanyl-substituted diketo-hydrocarbon which comprises heating a diketosubstituted hydrocarbon having a hydrogen atom directly rttached to a carbon atom to which two carbonyl carbon atoms are also directly attached, the hydrocarbon radicals joined to carbonyl carbon each containing not more than 18 carbon atoms, with a molar excess of biuret at a temperature of 100 C. to 250 C. whereby ammonia is formed and an allophanyl group is substituted for hydrogen on said carbon atom.

S. A process of producing allophanyl dibenzoyl methane which comprises heating at 100 C. to 250 C. and

under subatmospheric pressure dibenzoyl methane with a molar excess of biuret.

9. An allophanyl-substituted ketone of the formula wherein R represents a member of the group consisting of hydrogen and hydrocarbon radicals, R represents a member of the group consisting of hydrogen, hydrocarbon and radicals in which R is a hydrocarbon radical and R and R can together form a divalent hydrocarbon radical, said hydrocarbon radicals each containing not more than 18 carbon atoms.

10. Alpha allophanyl substituted keto hydrocarbon wherein the allophanyl group is directly linked to a carbon atom which is directly attached to a carbonyl carbon atom and the hydrocarbon radicals each contain not more than 18 carbon atoms.

ll. Alpha-allophanyl beta-diketone hydrocarbon wherea in the allophanyl group is directy linked to thecarbon 10 14. Allophanyl-substituted dicarboxylic acid ester of cals, each containing not more than 18 carbon atoms. the formula 16. Alpha-allophanyl dialkyl malonate wherein the alkyl groups contain not more than 18 carbon atoms. 1! H 5 References Cited in the file of this patent UNITED STATES PATENTS 893,308 Conrad July 14, 1908 2,304,369 Morgan et al Dec. 8, 1942 2,362,768 Morgan et a1. Nov. 14, 1944 wherein R represents a member of the group consisting of 2,379,486 Hill et a1 July 3 1945 the hydrogen atom and hydrocarbon radicals, and R and 2,400 394 De Groom et a1 May 14 1946 R represent hydrocarbon radicals, said hydrocarbon radi- 2 473577 De Groom et a1 June 21 1949 cals containing not more than 18 carbon atoms each. J

15. Allophanyl ester of the formula FOREIGN PATENTS 144,431 Germany Sept. 14, 1903 H g /COR 283,105 Germany Mar. 30, 1915 E OTHER REFERENCES 20 Chemical Abstracts, vol. 5 (1911), p. 2641.

Beilstein: Handbuch der Organischen Chemie, vol. wherein R and R" represent aliphatic hydrocarbon radi- III, 1st supplement (1929), p. 33. 

1. A PROCESS OF PRODUCING A MEMBER OF THE GROUP CONSISTING OF ALLOPHANYL-SUBSTITUTED KETONES AND CARBOXYLIC ACID ESTERS WHICH COMPRISES REACTING BIURET WITH A MEMBER OF THE GROUP CONSISTING OF MONOKETONES AND DIKETONES AND MONOCARBOXYLIC ACID ESTERS AND DICARBOXYLIC ACID ESTERS COMPOSED EXCLUSIVELY OF CARBON, HYDROGEN AND OXYGEN CHOSEN FROM THE GROUP CONSISTING OF ESTER AND KETO OXYGEN ATOMS, HAVING A TOTAL OF NOT MORE THAN 57 CARBON ATOMS IN THE MOLECULE AND HAVING A LABILE HYDROGEN ATOM ATTACHED TO A CARBON ATOM WHICH IS DIRECTLY LINKED TO A CARBONYL CARBON ATOM AT A TEMPERATURE OF ABOUT 50* C. TO ABOUT 350* C. WHEREBY AMMONIA IS FORMED AND AN ALLOPHANYL GROUP IS SUBSTITUTED FOR SAID LABILE HYDROGEN ATOM ON SAID CARBON ATOM. 